Liquid crystal display and manufacturing method thereof

ABSTRACT

A liquid crystal display, including: a first substrate and a second substrate; a liquid crystal layer; a first data line disposed on the first substrate; a pixel electrode disposed on the first substrate; and a common electrode disposed on the first substrate and overlapping at least a portion of the pixel electrode and the first data line. One of the pixel electrode and the common electrode includes a plurality of branch electrodes spaced apart from each other and the other of has an at least approximately planar shape that is substantially parallel to a surface of at least one of the first substrate and the second substrate. The display can also include a passivation layer having a dielectric constant of about 3.5 or less, and including a first portion disposed between the common electrode and the first data line.

CROSS-REFERENCE TO RELATED APPLICATION

This is a Continuation Application of U.S. patent application Ser. No.13/215,907 filed in the United States Patent & Trademark Office on Aug.23, 2011, which claims priority to, and the benefit of, both KoreanPatent Application No. 10-2011-0000241 filed in the Korean IntellectualProperty Office on Jan. 3, 2011 and Korean Patent Application No.10-2011-0044010 filed in the Korean Intellectual Property Office on May11, 2011, the entire contents of each of which are incorporated hereinby reference.

BACKGROUND OF THE INVENTION

(a) Field of the Invention

Embodiments of the present invention relate generally to flat paneldisplays. More specifically, embodiments of the present invention relateto liquid crystal display configurations and the manufacture thereof.

(b) Description of the Related Art

A liquid crystal display, which is one of the more common types of flatpanel displays currently in use, typically includes two sheets ofdisplay panels with field generating electrodes (such as a pixelelectrode and a common electrode, etc.) formed thereon, and a liquidcrystal layer interposed therebetween.

The liquid crystal display generates electric fields in a liquid crystallayer by applying voltage to the field generating electrodes, anddetermines the direction of liquid crystal molecules of the liquidcrystal layer by the generated electric field, thus controllingpolarization of incident light so as to display images.

Transmittance of the liquid crystal display may be increased withappropriate control of the liquid crystal molecules.

Meanwhile, each pixel electrode of the liquid crystal display isconnected with switching devices that are in turn connected with signallines such as gate lines, data lines, etc.

The switching device, which is a three-terminal device such as a thinfilm transistor or the like, transmits a data voltage to a pixelelectrode through its output terminal.

In some of these liquid crystal displays, the pixel electrode and thecommon electrode may be provided on a single display panel. In thiscase, light leakage may occur in the vicinity of the data lines, due tofield distortion caused by a capacitive coupling between the data lineand the pixel electrode.

The above information disclosed in this Background section is only forenhancement of understanding of the background of the invention andtherefore it may contain information that is not in the prior art.

SUMMARY OF THE INVENTION

The present invention increases the transmittance of a liquid crystaldisplay via a structure in which a pixel electrode and a commonelectrode are formed on a single display panel, prevents light leakagedue to a capacitive coupling between a data line and a pixel electrode,and reduces a load of the data line.

Further, the present invention has been made in an effort to increasefield generating efficiency of a liquid crystal layer in its displayarea.

An exemplary embodiment of the present invention provides a liquidcrystal display, including: a first substrate and a second substratefacing each other; a liquid crystal layer interposed between the firstsubstrate and the second substrate; a first data line disposed on thefirst substrate; a pixel electrode disposed on the first substrate forreceiving a data voltage from the first data line; and a commonelectrode disposed on the first substrate and overlapping at least aportion of the pixel electrode and the first data line. One of the pixelelectrode and the common electrode includes a plurality of branchelectrodes spaced apart from each other and the other of the pixelelectrode and the common electrode has an at least approximately planarshape.

Also included may be a passivation layer having a dielectric constant ofabout 3.5 or less and including a first portion disposed between thecommon electrode and the first data line.

A thickness of the passivation layer may be in a range from about 0.5 μmto about 3.0 μm.

The passivation layer may include an organic material.

The liquid crystal display may further include: a second data lineadjacent to the first data line and disposed in the same layer as thefirst data line, wherein the passivation layer may further include asecond portion disposed between the common electrode and the second dataline, and the first portion and the second portion may be spaced apartfrom each other.

The liquid crystal display may further include a second data lineadjacent to the first data line and disposed in the same layer as thefirst data line, wherein the passivation layer may further include athird portion disposed between the first data line and the second dataline and a thickness of the first portion may be greater than athickness of the second portion.

At least one of the pixel electrode and the common electrode may includea transparent conductive material.

Another exemplary embodiment of the present invention provides a methodof manufacturing a liquid crystal display, including: forming a dataconductor on a substrate, the data conductor including a first dataline; forming a pixel electrode on the substrate; and forming a commonelectrode on the substrate, the common electrode overlapping at least aportion of the pixel electrode and the first data line. One of the pixelelectrode and the common electrode includes a plurality of branchelectrodes spaced apart from each other and the other of the pixelelectrode and the common electrode has an at least approximately planarshape.

The forming of the passivation layer may further include: depositing anorganic material between the common electrode and the first data line;and forming a passivation pattern by exposing the deposited organicmaterial using a photo mask, the passivation pattern including a secondportion overlapping the first data line and a third portion having athickness less than that of the second portion.

The photo mask may include a transparent area configured to transmitlight, an opaque area configured to block light, and a translucent areaconfigured to transmit a portion of incident light.

The forming of the data conductor may further include forming a seconddata line adjacent to the first data line and the second portion of thepassivation pattern may overlap the second data line.

The manufacturing method of a liquid crystal display may furtherinclude: etching the passivation pattern and ashing the passivationpattern.

The ashing of the passivation pattern may include removing the thirdportion.

The manufacturing method of a liquid crystal display may furtherinclude: forming an insulating layer under the passivation layer,wherein the etching of the passivation pattern may further includeetching the insulating layer.

A thickness of the passivation layer may be in a range from about 0.5 μmto about 3.0 μm, and at least one of the pixel electrode and the commonelectrode may include a transparent conductive material.

Another exemplary embodiment of the present invention provides a liquidcrystal display, comprising: a first substrate and a second substratefacing each other; a liquid crystal layer interposed between the firstsubstrate and the second substrate; a first data line disposed on thefirst substrate; a common electrode disposed on the first data line andoverlapping the first data line, the common electrode having an at leastapproximately planar shape; a pixel electrode disposed on the commonelectrode for receiving a data voltage from the first data line, thepixel electrode including a plurality of branch electrodes spaced apartfrom each other; and a passivation layer disposed on the firstsubstrate, the passivation layer having a dielectric constant of about3.5 or less, the passivation layer further having a first portiondisposed between the first data line and the common electrode.

A thickness of the passivation layer may be in a range from about 0.5 μmto about 3.0 μm.

The passivation layer may include an organic material.

The liquid crystal display may further comprise a second data lineadjacent to the first data line and disposed in the same layer as thefirst data line, wherein the passivation layer further includes a secondportion disposed between the common electrode and the second data line,and the first portion and the second portion are spaced apart from eachother.

Another exemplary embodiment of the present invention provides a methodof manufacturing a liquid crystal display, the method comprising:forming a data conductor on a substrate, the data conductor including afirst data line; forming a common electrode on the first data line, thecommon electrode overlapping the first data line; forming a pixelelectrode on the common electrode; forming a passivation layer having afirst portion disposed between the first data line and the commonelectrode and having a dielectric constant of about 3.5 or less, whereinthe pixel electrode includes a plurality of branch electrodes spacedapart from each other and the common electrode has an at leastapproximately planar shape.

The forming a passivation layer may further include: depositing anorganic material over the first data line before the forming the commonelectrode; and forming a passivation pattern by exposing the depositedorganic material using a photo mask, the passivation pattern including asecond portion overlapping the first data line and a third portionhaving a thickness less than that of the second portion.

The forming a data conductor may further include forming a second dataline adjacent to the first data line, the second portion of thepassivation pattern overlapping the second data line.

The method may further comprise etching the passivation pattern, andashing the passivation pattern.

The ashing the passivation pattern may further include removing thethird portion.

Another exemplary embodiment of the present invention provides a liquidcrystal display, comprising: a first substrate and a second substratefacing each other; a liquid crystal layer interposed between the firstsubstrate and the second substrate; a first data line disposed on thefirst substrate; a common electrode disposed on the first substrate andoverlapping the first data line; and a pixel electrode disposed on thecommon electrode for receiving a data voltage from the first data line,the pixel electrode including a plurality of branch electrodes spacedapart from each other.

The liquid crystal display may further comprise a passivation layerincluding a first portion disposed between the first data line and thecommon electrode, the passivation layer comprising an organic material.

The passivation layer may have a dielectric constant of about 3.5 orless.

A thickness of the passivation layer may be in a range from about 0.5 μmto about 3.0 μm.

The liquid crystal display may further comprise a second data lineadjacent to the first data line and disposed in the same layer as thefirst data line, wherein the passivation layer further includes a secondportion disposed between the common electrode and the second data line,and the first portion and the second portion are spaced apart from eachother.

The passivation layer may further include a third portion connecting thefirst portion and the second portion so that the passivation layer mayat least partially cover the first data line and the second data line.

The liquid crystal display may further comprise a light blocking memberdisposed on the second substrate.

The light blocking member may be positioned between two adjacent pixelelectrodes, the two adjacent pixel electrodes being disposed on opposingsides of the first data line.

A width of the light blocking member may be equal to or less than adistance between the two adjacent pixel electrodes.

The common electrode may have an at least approximately planar shapethat is substantially parallel to a surface of at least one of the firstsubstrate and the second substrate.

Another exemplary embodiment of the present invention provides a liquidcrystal display, comprising: a first substrate and a second substratefacing each other; a liquid crystal layer disposed between the firstsubstrate and the second substrate; a first data line disposed on thefirst substrate; a first pixel electrode disposed on the first substrateand in electrical communication with the first data line so as to beconfigured to receive a data voltage from the first data line; a commonelectrode disposed on the first substrate and overlapping the pixelelectrode and the first data line; and a first passivation layerdisposed on the first data line and including an organic material,wherein one of the first pixel electrode and the common electrodeincludes a plurality of branch electrodes spaced apart from each other,and the other of the first pixel electrode and the common electrode hasan at least approximately planar shape that is substantially parallel toa surface of at least one of the first substrate and the secondsubstrate, and the first passivation layer includes a first portioncovering the first data line.

The liquid crystal display may further comprise a second data lineadjacent to the first data line, wherein the first passivation layerfurther includes a second portion covering the second data line, and thefirst portion and the second portion are spaced apart from each other.

The first passivation layer may be disposed between the first data lineand the common electrode.

The liquid crystal display may further comprise: a second pixelelectrode adjacent to the first pixel electrode, and a light blockingmember that covers an area between the first pixel electrode and thesecond pixel electrode.

A portion of the light blocking member positioned between the firstpixel electrode and the second pixel electrode has a width that may beequal to or smaller than a distance between the first pixel electrodeand the second pixel electrode.

The first pixel electrode may be disposed on the common electrode, andthe first pixel electrode may include a plurality of branch electrodesand the common electrode has an approximately planar shape.

The thickness of the first portion may be thicker than that of the thirdportion. The thickness of the first passivation layer may be in a rangefrom about 0.5 μm to about 3.0 μm.

According to the exemplary embodiments of the present invention, byforming an electrode having a generally planar shape and an electrodeincluding branch electrodes on a single substrate, the efficiency of theliquid crystal molecules motion may be increased, thereby making itpossible to increase the transmittance of the liquid crystal display.

Further, a portion of the common electrode covers the data line toreduce light leakage, and by interposing a passivation layer having lowpermittivity or a passivation layer including an organic materialbetween the data line and the common electrode, the parasiticcapacitance of the data line and the common electrode may be decreased,thereby making it possible to reduce the signal delay of the data line.

In addition, the passivation layer is disposed only between the dataline and the common electrode or, alternatively, the passivation layerdisposed in the display area is formed to be thin, thereby making itpossible to increase the field generating efficiency in the liquidcrystal layer and to prevent defects of the alignment layer or wiringdefects due to a step difference in height due to the passivation layer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a layout view of one pixel of a liquid crystal displayaccording to an exemplary embodiment of the present invention;

FIGS. 2 and 3 each show an exemplary embodiment of cross-sectional viewstaken along line II-II and line III-III of the liquid crystal display ofFIG. 1;

FIGS. 4 and 5 each show another exemplary embodiment of cross-sectionalviews taken along line II-II and line III-III of the liquid crystaldisplay of FIG. 1;

FIG. 6 is a layout view of one pixel of the liquid crystal displayaccording to the exemplary embodiment of the present invention;

FIGS. 7 and 8 each are cross-sectional views taken along line VII-VIIand line VIII-VIII of the liquid crystal display of FIG. 6;

FIG. 9 is a layout view of one pixel of the liquid crystal displayaccording to the exemplary embodiment of the present invention;

FIGS. 10 and 11 each are cross-sectional views taken along line X-X andline XI-XI of the liquid crystal display of FIG. 9;

FIG. 12 is a layout view of one pixel of the liquid crystal displayaccording to the exemplary embodiment of the present invention;

FIGS. 13 and 14 each are cross-sectional views taken along lineXIII-XIII and line XIV-XIV of the liquid crystal display of FIG. 12;

FIGS. 15, 18, 21 and 24 are layout views sequentially showing the liquidcrystal display at the intermediate step of a manufacturing method ofthe liquid crystal display shown in FIGS. 1 to 5 according to anexemplary embodiment of the present invention;

FIGS. 16, 19, 22, 25, 27, and 29 are sequential cross-sectional viewstaken along line XVI-XVI, line XIX-XIX, line XXII-XXII, and line XXV-XXVof the liquid crystal display of FIGS. 15, 18, 21, and 24;

FIGS. 17, 20, 23, 26, 28, and 30 are sequential cross-sectional viewstaken along line XVII-XVII, line XX-XX, line XXIII-XXIII, and lineXXVI-XXVI of the liquid crystal display of FIGS. 15, 18, 21, and 24;

FIG. 31 is a plan view of a pixel electrode or a common electrodeaccording to another exemplary embodiment of the present invention;

FIG. 32 is a layout view of one pixel of a liquid crystal displayaccording to an exemplary embodiment of the present invention;

FIGS. 33 and 34 each are cross-sectional views taken along lineXXXIII-XXXIII and line XXXIV-XXXIV of the liquid crystal display of FIG.32, according to the exemplary embodiment of the present invention;

FIGS. 35 and 36 each are cross-sectional views taken along lineXXXIII-XXXIII and line XXXIV-XXXIV of the liquid crystal display of FIG.32, according to another exemplary embodiment of the present invention;

FIGS. 37 and 38 each are cross-sectional views taken along lineXXXIII-XXXIII and line XXXIV-XXXIV of the liquid crystal display of FIG.32, according to another exemplary embodiment of the present invention;

FIG. 39 is a layout view of one pixel of a liquid crystal displayaccording to an exemplary embodiment of the present invention;

FIGS. 40 and 41 each are cross-sectional views taken along line XL-XLand line XLI-XLI of the liquid crystal display of FIG. 39, according toan exemplary embodiment of the present invention;

FIGS. 42 and 43 each are cross-sectional views taken along line XL-XLand line XLI-XLI of the liquid crystal display of FIG. 39, according toanother exemplary embodiment of the present invention;

FIGS. 44 and 45 each are cross-sectional views taken along line XL-XLand line XLI-XLI of the liquid crystal display of FIG. 39, according toanother exemplary embodiment of the present invention; and

FIGS. 46, 47, 48, 49, and 50 each are layout views of a liquid crystaldisplay according to an exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The present invention will be described more fully hereinafter withreference to the accompanying drawings, in which exemplary embodimentsof the invention are shown. As those skilled in the art would realize,the described embodiments may be modified in various different ways, allwithout departing from the spirit or scope of the present invention.

In the drawings, the thickness of layers, films, panels, regions, etc.,are exaggerated for clarity. Like reference numerals designate likeelements throughout the specification. It will be understood that whenan element such as a layer, film, region, or substrate is referred to asbeing “on” another element, it can be directly on the other element orintervening elements may also be present. In contrast, when an elementis referred to as being “directly on” another element, there are nointervening elements present.

First, a liquid crystal display according to an exemplary embodiment ofthe present invention will be described with reference to FIGS. 1, 2, 3,4, and 5.

FIG. 1 is a layout view of one pixel of a liquid crystal displayaccording to an exemplary embodiment of the present invention, FIGS. 2and 3 respectively show cross-sectional views taken along line II-II andline III-III of one embodiment of the liquid crystal display of FIG. 1,and FIGS. 4 and 5 respectively show cross-sectional views taken alongline II-II and line III-III of another embodiment of the liquid crystaldisplay of FIG. 1.

The liquid crystal display of these embodiments includes a lower displaypanel 100 and an upper display panel 200 facing each other, as well as aliquid crystal layer 3 interposed between the two display panels 100 and200.

First, the lower display panel 100 will be described below.

A plurality of gate conductors, including a plurality of gate lines 121and a plurality of common voltage lines 125, are formed on an insulatingsubstrate 110.

The gate lines 121 transmit gate signals and substantially extend in ahorizontal direction. Each gate line 121 includes a plurality of gateelectrodes 124 that protrude substantially upwardly.

The common voltage line 125 may transmit a predetermined voltage such ascommon voltage Vcom, may substantially extend in a horizontal direction,and may be substantially parallel with the gate line 121.

Each common voltage line 125 may include a plurality of extensions 126.

A gate insulating layer 140 is formed on the gate conductors 121 and125. The gate insulating layer 140 may be made of inorganic insulatingmaterial or the like, examples being silicon nitride (SiNx), siliconoxide (SiOx), or the like.

A plurality of linear semiconductors 151 are formed on the gateinsulating layer 140. Each linear semiconductor 151 substantiallyextends in a vertical direction and the plurality of semiconductorprotrusions 154 extends toward the gate electrode 124 from each linearsemiconductor 151.

A plurality of linear ohmic contacts 161 and a plurality of island ohmiccontacts 165 are formed on the linear semiconductor 151. The linearohmic contact 161 has a plurality of protrusions 163 extending towardthe gate electrode 124. The protrusions 163 and the island ohmiccontacts 165 are formed in pairs facing each other over the gateelectrode 124, and are disposed on the semiconductor protrusion 154. Theohmic contacts 161 and 165 are made of a material such as n+hydrogenated amorphous silicon, etc., doped with n-type impurity such asphosphorus, etc., at high concentration, or may be made of silicide.

Data conductors, including a plurality of data lines 171 and a pluralityof drain electrodes 175, are formed on the ohmic contacts 161 and 165.

The data lines 171 transmit data signals and substantially extend in avertical direction, to intersect the gate lines 121 and the commonvoltage line 125. Each data line 171 includes a plurality of sourceelectrodes 173 extending toward the gate electrode 124.

The drain electrode 175 includes a generally bar-shaped end facing thesource electrode 173 and another end having a wider area than thebar-shaped end.

The gate electrode 124, the source electrode 173, and the drainelectrode 175 collectively form a switching device, i.e., a thin filmtransistor (TFT), together with the semiconductor protrusion 154.

The linear semiconductor 151 may have substantially the same planarshape as the data line 171, the drain electrode 175, and the ohmiccontacts 161 and 165 disposed thereunder, except for the semiconductorprotrusion 154 on which the thin film transistor is disposed. Throughoutthe description and the claims, “planar shape” may mean that the elementin question has a particular shape in a plane which is substantiallyparallel to a surface of the insulating substrate 110. In other words,“planar shape” may mean that the related element has a particular shapein a plane which is substantially parallel to a plane including two datalines 171, a plane including two gate lines 121, or a plane includingboth the data line 171 and the gate line 121.

Pixel electrodes 191 are formed on the data conductors 171 and 175 andthe exposed semiconductor protrusion 154.

The pixel electrode 191 may be made of a transparent conductive materialsuch as ITO, IZO, or the like.

The pixel electrode 191 is disposed on the drain electrode 175 of thethin film transistor to cover and directly contact a portion of thedrain electrode 175, and also includes a portion contacting the gateinsulating layer 140. The pixel electrode 191 receives the data voltagefrom the drain electrode 175.

Alternatively, a passivation layer (not shown) made of an inorganicmaterial or an organic material may be further disposed on the dataconductors 171 and 175 and the exposed semiconductor protrusion 154, andthe pixel electrode 191 may be disposed on the passivation layer. Inthis case, the pixel electrode 191 may receive the data voltage from thedrain electrode 175 through a contact hole (not shown) in thepassivation layer.

The pixel electrode 191 has a planar shape that fills most of the areasurrounded by the gate line 121 and the data line 171.

The general shape of the pixel electrode 191 may be a rectangular shapehaving four sides approximately parallel with the gate line 121 and thedata line 171. Edges of the pixel electrode 191 lying near the thin filmtransistor may be chamfered, but the shape of the pixel electrode 191 isnot limited thereto.

A first passivation layer 180 a is formed on the pixel electrode 191,the data conductors 171 and 175, and the exposed semiconductorprotrusion 154. The first passivation layer 180 a may be made of aninorganic insulating material or an organic insulating material.

A number of contact holes 182 are formed on the first passivation layer180 a and the gate insulating layer 140 in order to expose a portion ofthe common voltage line 125, for example, a portion of the extension126.

Referring to FIGS. 2 and 3, a second passivation layer 180 c is formedon the first passivation layer 180 a. The second passivation layer 180 caccording to the exemplary embodiment is formed along the data line 171,covering the data line 171.

The second passivation layer 180 c may be made of an organic material oran inorganic material, and its relative dielectric constant may be about3.5 or less. There may be about 10% deviation in the relative dielectricconstant of the second passivation layer 180 c, according to themeasuring method used. When the second passivation layer 180 c includesa colored material such as a material for color filters, the relativedielectric constant of the second passivation layer 180 c may beincreased to about 4.5 considering the relative dielectric constant ofthe pigment or dye included in the colored material. In particular, itis preferable that the dielectric constant of the second passivationlayer 180 c is lower than that of the first passivation layer 180 a.Comparing the relative permittivity, the dielectric constant of thesecond passivation layer 180 c may be lower than that of the lower firstpassivation layer 180 a or the gate insulating layer 140.

The thickness of the second passivation layer 180 c may be in a rangefrom about 0.5 μm to about 3.0 μm. The lower the dielectric constant ofthe second passivation layer 180 c is, the thinner its thickness may be.

Alternatively, referring to FIGS. 4 and 5, a second passivation layer180 b is formed on the first passivation layer 180 a.

The second protective layer 180 b is formed on the whole surface of thefirst passivation layer 180 a, and thus, it is also disposed between twoadjacent data lines 171.

Further, the contact hole 182 of the first passivation layer 180 a andthe gate insulating layer 140 is extended to the second passivationlayer 180 b so that the contact hole 182 is formed through the gateinsulating layer 140, the first passivation layer 180 a and the secondpassivation layer 180 b.

The second passivation layer 180 b covers the data line 171, andincludes a thicker portion 180 c′ disposed along the data line 171.

In the exemplary embodiment shown in FIGS. 4 and 5, the firstpassivation layer 180 a may be omitted.

In addition, the characteristics of the second passivation layer 180 bare generally the same as the characteristics of the second passivationlayer 180 c shown in FIGS. 2 and 3 described above.

The plurality of common electrodes 131 are formed on the secondpassivation layers 180 c and 180 b.

The common electrode 131 may be made of a transparent conductivematerial such as ITO, IZO, or the like.

Each common electrode 131 includes vertical parts 135 covering the dataline 171 and the second passivation layers 180 c and 180 b, a pluralityof branch electrodes 133 spaced apart from each other while beingdisposed between the two vertical parts 135, as well as a lowerhorizontal part 132 a and an upper horizontal part 132 b connecting theends of the plurality of branch electrodes 133.

The vertical part 135 is substantially parallel with the data line 171and overlaps the data line 171 so as to cover the data line 171. Thelower and upper horizontal parts 132 a and 132 b may substantiallyparallel with the gate line 121.

The plurality of branch electrodes 133 may be substantially parallelwith each other and form a bevel angle with respect to the extendingdirection of the gate line 121, wherein the bevel angle may be 45degrees or more.

The upper branch electrode 133 and the lower branch electrode 133 maygenerally have an inversion symmetry to each other relative to thevirtual horizontal central line of the common electrode 131.

The adjacent common electrodes 131 are connected to each other through avertical part 135.

The common electrode 131 partially overlaps with the pixel electrode191. In particular, at least two adjacent branch electrodes 133 of thecommon electrode 131 overlap with the pixel electrode 191.

The common electrode 131 receives a predetermined voltage, such as thecommon voltage Vcom, from the common voltage line 125 through thecontact hole 182.

Next, the upper display panel 200 will be described. A light blockingmember 220 and a color filter 230 are formed on an insulating substrate210.

The light blocking member 220 is disposed between adjacent pixelelectrodes 191 and prevents light leakage between the pixel electrodes191, and defines an opening area facing the pixel electrode 191. Thelight blocking member 220 includes a portion covering the area betweentwo adjacent pixel electrodes 191 that are disposed on either side ofthe data line 171. Therefore, the light blocking member 220 may coverthe data line 171 extending along the area between the two adjacentpixel electrodes 191. The width of the light blocking member 220 may begenerally equal to or smaller than a distance between the two adjacentpixel electrodes 191. For example, a distance between an edge of thelight blocking member 220 and an edge of the adjacent pixel electrode191 may be 0 (zero) or more (when viewed along a normal to the uppersurface of substrate 110), and may be smaller than a distance betweenthe two adjacent pixel electrodes 191. The light blocking member 220prevents light from leaking out between the adjacent pixel electrodes191.

The color filter 230 is formed in the area surrounded by the lightblocking member 220, and may extend long along a column of the pixelelectrode 191. Each color filter 230 may display one of a primary colorsuch as red, green, and blue, or the like.

An overcoat 250 may be further formed on the light blocking member 220and the color filter 230.

Alignment layers 11 and 21 may be applied on the inner surfaces of thetwo display panels 100 and 200 (i.e., on the surfaces of panels 100, 200that face each other), and may be horizontal alignment layers.

In the exemplary embodiment shown in FIG. 1, the branch electrode 133 ofthe common electrode 131 is inclined so as to be closer to a verticaldirection, i.e. the direction along which the data line 171 extends. Thealignment direction of the alignment layers 11 and 21 may be a verticaldirection.

The liquid crystal layer 3 interposed between the lower display panel100 and the upper display panel 200 includes a liquid crystal molecule31, wherein the liquid crystal molecule 31 may be aligned so that amajor axis thereof is formed to be generally horizontal with respect tothe surfaces of the two display panels 100 and 200 when an electricfield is not present.

When a data voltage is applied to the pixel electrode 191 and a commonvoltage Vcom is applied to common electrode 131, an electric field isgenerated in the liquid crystal layer 3, thereby determining thedirection of the liquid crystal molecule 31 of the liquid crystal layer3 to display the corresponding image.

In particular, the pixel electrode 191 is substantially planar in thedisplay area surrounded by the data line 171 and the gate line 121, suchthat it can control the directions of the liquid crystal molecules 31 inmost of the display area (other than the portion around the central lineof the branch electrodes 133 of the common electrode 131) by theelectric field represented by the arrow in FIG. 3, thereby increasingthe transmittance of the liquid crystal display. Particularly, sinceelectric fields may be generated even above the branch electrodes 133 ofthe common electrode due to the pixel electrode 191 having a planarshape, the transmittance of the liquid crystal display according to thepresent embodiment of the present invention may be further increased, ascompared to pixel electrodes that have branches alternatingly disposedwith the branch electrodes of the common electrode (IPS mode).

In the exemplary embodiment of the present invention, the vertical part135 of the common electrode 131 overlaps the data line 171 to cover thedata line 171 in a width direction, thereby making it possible to reducecrosstalk between the data line 171 and the pixel electrode 191 and toreduce light leakage due to the parasitic capacitance between the dataline 171 and the adjacent pixel electrode 191. That is, at least aportion of the vertical part 135 of the common electrode 131 is placedbetween the pixel electrode 191 and data line 171, reducing crosstalkand light leakage between the data line 171 and pixel electrode 191.

In addition, according to the exemplary embodiment of the presentinvention, the second passivation layers 180 c and 180 b, having lowpermittivity, are interposed between the data line 171 and the verticalpart 135 of the upper common electrode 131, thereby making it possibleto lower the parasitic capacitance between the data line 171 and theupper common electrode 131, so as to reduce the signal delay of the dataline 171.

In particular, as described in the exemplary embodiment of FIGS. 2 and3, the second passivation layer 180 c is formed only on the upperportion of the data line 171. Alternatively, as described in theexemplary embodiment of FIGS. 4 and 5, the second passivation layer 180b is thicker above, or proximate to, the data line 171 and thinnerelsewhere. In this manner, the pixel electrode 191 disposed on the lowerlayer of the second passivation layers 180 c and 180 b can increase thefield generating efficiency of the display.

In addition, when the permittivity of the second passivation layers 180c and 180 b is reduced, the thickness thereof may be further reduced,such that the field generating efficiency may be further increased inthe display area, thereby making it possible to further increase thetransmittance.

This configuration also acts to prevent defects of the alignment layerdue to a step difference in height, and wiring defects such asdisconnections, by lowering the thickness of the second passivationlayers 180 c and 180 b.

In the exemplary embodiment of the present invention, the position ofthe second passivation layers 180 c and 180 b that have a relatively lowdielectric constant is not limited to those shown in the exemplaryembodiments described in FIGS. 1 to 5. In particular, they may bedisposed in any layer between the data line 171 and the common electrode131.

Next, a liquid crystal display according to another exemplary embodimentof the present invention will be described with reference to FIGS. 6, 7,and 8.

The same components as the above-mentioned exemplary embodiments aredenoted by the same reference numerals, and description thereof will belargely omitted.

FIG. 6 is a layout view of one pixel of the liquid crystal displayaccording to this exemplary embodiment of the present invention, andFIGS. 7 and 8 each are cross-sectional views taken along line VII-VIIand line VIII-VIII of the liquid crystal display of FIG. 6.

This exemplary embodiment of the present invention is similar to theexemplary embodiment shown in FIGS. 1 to 5, but with differences in thestructure of the data line 171, the pixel electrode 191, the commonelectrode 131, and the interlayer insulating layer lying therebetween.

Differences from the exemplary embodiments shown in FIGS. 1 to 5 will bemainly described.

The data line 171 according to the exemplary embodiment of the presentinvention is bent in periodic manner, thus forming a bevel angle withrespect to the extending direction of the gate line 121.

The bevel angle of the data line 171 and the extending direction of thegate line 121 may be about 45 degrees or more.

The first passivation layer 180 a is formed on the data conductors 171and 175 and the exposed semiconductor protrusion 154, and the pixelelectrode 191 is formed thereon.

The first passivation layer 180 a includes the contact hole 181 exposinga portion of the drain electrode 175, and the pixel electrode 191 iselectrically connected to the drain electrode 175 through the contacthole 181.

The pixel electrode 191 has a generally planar shape filling most of thearea surrounded by the gate line 121 and the data line 171, and has aside almost parallel with the gate line 121 and the data line 171.

Vertical sides of the pixel electrode 191 are bent similar to that ofthe data line 171 so as to lie generally parallel to the data lines 171,and both sides may be chamfered, although the invention is notnecessarily limited to such configurations.

The second passivation layer 180 b is formed on the pixel electrode 191,and the common electrode 131 is formed thereon.

The plurality of contact holes 182 are formed on the gate insulatinglayer 140, the first passivation layer 180 a, and the second passivationlayer 180 b in order to expose at least a portion of the extension 126of the common voltage line 125.

The common electrode 131 is electrically connected to the common voltageline 125 through the contact hole 182 to receive a predeterminedvoltage, such as the common voltage Vcom, etc., from the common voltageline 125.

The common electrode 131 includes vertical parts 135 bent whileoverlapping the data line 171 to cover the data line 171 in a widthdirection, and a plurality of branch electrodes 133 spaced apart fromeach other while being disposed between the two vertical parts 135 andextending substantially parallel to the vertical part 135, as well as alower horizontal part 132 a and an upper horizontal part 132 bconnecting the ends of the plurality of branch electrodes 133.

The vertical part 135 of the common electrode 131 overlaps with the dataline 171 to cover the data line 171 in a width direction.

The first passivation layer 180 a and the second passivation layer 180 bare disposed between the data line 171 and the common electrode 131. Atleast one of these passivation layers may be made of an organicinsulating material or an inorganic insulating material such as SiOC, ora compound of the organic insulating material and the inorganicinsulating material, etc., and the dielectric constant thereof may beabout 3.5 or less. There may be about 10% deviation in such relativedielectric constant of the at least one of the passivation layers.

The dielectric constant of the first passivation layer 180 a or thesecond passivation layer 180 b may be lower than the dielectric constantof the gate insulating layer 140.

The thickness of the first passivation layer 180 a or the secondpassivation layer 180 b may be in a range from about 0.5 μm to about 3.0μm.

In addition, any one or more characteristics and effects of the secondpassivation layers 180 c and 18 b of the exemplary embodiments of FIGS.1 and 5 described above may also be applied to the first passivationlayer 180 a or the second passivation layer 180 b of this embodiment.

Next, the liquid crystal display according to a further embodiment ofthe present invention will be described with reference to FIGS. 9, 10,and 11.

The same components as the above-mentioned exemplary embodiments aredenoted by the same reference numerals, and any redundant descriptionthereof will be omitted.

FIG. 9 is a layout view of one pixel of the liquid crystal display ofthis embodiment of the present invention, and FIGS. 10 and 11 each arecross-sectional views taken along line X-X and line XI-XI of the liquidcrystal display of FIG. 9.

This embodiment of the present invention is similar to the exemplaryembodiment shown in FIGS. 1 to 5, but contains differences in thestructure of the pixel electrode 191, the common electrode 131, and theinterlayer insulating layer positioned therebetween.

Differences between the exemplary embodiments shown in FIGS. 1 to 5 willprimarily be described.

The first passivation layer 180 a is formed on the data conductors 171and 175 and the exposed semiconductor protrusion 154, and a thirdpassivation layer 180 d is formed thereon. The third passivation layer180 d is formed along the data line 171, to cover the data line 171.

The characteristics of the third passivation layer 180 d aresubstantially the same as those of the second passivation layer 180 b ofthe exemplary embodiment of FIGS. 1 to 3 described above, and thereforeany detailed description thereof will be omitted.

The third passivation layer 180 d may be formed on substantially theentire surface of the substrate 110 as well as between the two adjacentdata lines 171, like the second passivation layer 180 b of theembodiment of FIGS. 1, 4, and 5 described above. In this case, the thirdpassivation layer 180 d may be thicker where it overlaps the data line171.

A common electrode 131 m is formed on the first passivation layer 180 aand the third passivation layer 180 d.

The first passivation layer 180 a and the gate insulating layer 140include the contact hole 184 which exposes at least a portion of theextension 126 of the common voltage line 125, and the common electrode131 m is electrically connected with the common voltage line 125 throughthe contact hole 184 to receive a predetermined voltage such as thecommon voltage Vcom from the common voltage line 125.

The common electrode 131 m has a generally planar shape and is formed onsubstantially the entire surface of the substrate 110 over the pluralityof pixels, unlike the above-mentioned exemplary embodiment.

The second passivation layer 180 b is formed on the common electrode 131m, and the pixel electrode 191 m is formed thereon.

The first passivation layer 180 a and the second passivation layer 180 bare provided with a plurality of contact holes 183 to expose a portionof the drain electrode 175.

The pixel electrode 191 m includes a plurality of branch electrodes 193m that extend substantially parallel with each other and that are spacedapart from each other, as well as lower and upper horizontal parts 192 mconnecting the end portions of the branch electrodes 193 m.

When a data voltage is applied to the pixel electrode 191 m and a commonvoltage is applied to the common electrode 131 m, an electric field isgenerated in the liquid crystal layer 3.

The pixel electrode 191 m of this embodiment of the present invention atleast partially overlaps the common electrode 131 m. In particular, atleast two adjacent branch electrodes 193 m of the pixel electrode 191 moverlap the planar-shaped common electrode 131 m.

In this embodiment of the present invention, the pixel electrode 191 mis disposed on the common electrode 131 m, and the common electrode 131m covers a number of data lines 171 at a time and also overlaps the datalines 171.

Therefore, as in the above exemplary embodiment, it is possible toreduce crosstalk between the data line 171 and the pixel electrode 191and to reduce light leakage due to a parasitic capacitance between thedata line 171 and the neighboring pixel electrode 191.

In addition, since the third passivation layer 180 d has a relativelylow permittivity and is interposed between the data line 171 and thecommon electrode 131 m, the parasitic capacitance between the data line171 and the common electrode 131 m may be decreased, thereby making itpossible to reduce the signal delay of the data line 171.

Further, characteristics and effects of the third passivation layer 180d may be substantially the same as the second passivation layers 180 cand 180 b of the exemplary embodiment shown in FIGS. 1 to 5 describedabove.

Unlike the above-described several embodiments, the common electrodetransmitting the common voltage may be disposed directly on thesubstrate 110, or may be disposed in a layer under the data line 171.Even in this case, the common electrode may be formed to overlap thedata line, so as to prevent light leakage of in liquid crystal display.Additionally, the insulating layer may have a relatively low dielectricconstant and may be disposed between the data line and the commonelectrode to reduce the signal delay of the data line.

In addition, the field generating efficiency may be increased in theliquid crystal layer, and defects due to a step difference may bereduced, by reducing the thickness of the insulating layer disposedbetween the data line and the common electrode.

Next, a liquid crystal display according to a still further embodimentof the present invention will be described with reference to FIGS. 12,13, and 14.

The same components as the above-mentioned exemplary embodiments aredenoted by the same reference numerals, and description thereof will beomitted.

FIG. 12 is a layout view of one pixel of the liquid crystal displayaccording to this embodiment of the present invention, and FIGS. 13 and14 are cross-sectional views taken along line XIII-XIII and lineXIV-XIV, respectively, of the liquid crystal display of FIG. 12.

The liquid crystal display according to the present exemplary embodimentof the present invention is similar to the exemplary embodiment shown inFIGS. 9 to 11, but contains differences in the structure of the dataline 171, the pixel electrode 191, the common electrode 131, and theinterlayer insulating layer lying therebetween.

Differences from the exemplary embodiments shown in FIGS. 9 to 11 willprimarily be explained.

The data line 171 of this embodiment of the present invention is bent ineach pixel area, to form a bevel angle with respect to the gate line121.

The bevel angle of the data line 171 may be about 45 degrees or more.

The first passivation layer 180 a is formed on the data conductors 171and 175 and the exposed semiconductor protrusion 154, and the commonelectrode 131 m is formed thereon.

The first passivation layer 180 a and the gate insulating layer 140include the contact hole 184 to expose at least a portion of theextension 126 of the common voltage line 125, and the common electrode131 m is electrically connected with the common voltage line 125 throughthe contact hole 184 to receive a predetermined voltage, such as thecommon voltage Vcom, from the common voltage line 125.

The common electrode 131 m has a generally planar shape and is formed onsubstantially the entire surface of the substrate 110 over the pluralityof pixels.

The second passivation layer 180 b is formed on the common electrode 131m, and the pixel electrode 191 m is formed thereon.

The first passivation layer 180 a and the second passivation layer 180 bare provided with the plurality of contact holes 183 to expose a portionof the drain electrode 175, and the pixel electrode 191 m iselectrically connected with the drain electrode 175 through the contacthole 183 so as to receive the data voltage.

The pixel electrode 191 m includes the plurality of branch electrodes193 m spaced apart from each other while extending substantiallyparallel with each other, as well as the lower and upper horizontalparts 192 m connecting the upper and lower ends of the branch electrode193 m.

The branch electrode 193 m of the pixel electrode 191 m may be bentalong the data line 171, so that the branch electrode 193 m have largelythe same shape as the data line 171 (that is, the electrodes 193 mremain parallel to the data lines 171 in their bent portions).

A data voltage and common voltage are applied to the pixel electrode 191m and common electrode 131 m respectively, to generate an electric fieldin the liquid crystal layer 3.

In the present exemplary embodiment, the pixel electrode 191 m isdisposed on the common electrode 131 m, and the common electrode 131 mcovers multiple data lines 171.

Therefore, similar to the above exemplary embodiment, it is possible toreduce crosstalk between the data line 171 and the pixel electrode 191,and to reduce light leakage due to a parasitic capacitance between thedata line 171 and the adjacent pixel electrode 191.

In addition, the first passivation layer 180 a (disposed between thedata line 171 and the common electrode 131 m) may be made of an organicinsulating material or an inorganic insulating material, of which thedielectric constant may be about 3.5 or less. There may be about 10%deviation in such relative dielectric constant of the second passivationlayer 180 a, depending on the measuring method employed.

The dielectric constant of the first passivation layer 180 a may belower than the dielectric constant of either one or both of the gateinsulating layer 140 and the second passivation layer 180 b.

In the exemplary embodiment of the present invention, the thickness ofthe first passivation layer 180 a may be in a range from about 0.5 μm toabout 3.0 μm, and the thickness of the first passivation layer 180 a maybe generally proportional to its dielectric constant. That is, the lowerthe dielectric constant of the first passivation layer 180 a is, thethinner its thickness may be.

As described above, the signal delay of the data line 171 may be reducedby lowering the dielectric constant of the first passivation layer 180a.

An additional passivation layer (not shown) extending along the dataline 171 and covering the data line 171 may be further formed on thefirst passivation layer 180 a. The additional passivation layer mayfurther include a portion covering the area between two data lines 171.

In this case, the passivation layer (not shown) covering the data line171 may have a dielectric constant of about 3.5 or less. There may beabout 10% deviation in such relative dielectric constant of thepassivation layer, depending on the measuring method used.

In addition, various characteristics and effects of the thirdpassivation layer 180 d of the exemplary embodiment shown in FIGS. 9 to11 described above may be applied to the first passivation layer 180 aof the exemplary embodiment of the present invention.

Hereinafter, a method of manufacturing a lower display panel of theliquid crystal display of the present invention will be described.

A method of manufacturing a lower display panel 100 of the liquidcrystal display shown in FIGS. 1 to 5 will be described with referenceto FIGS. 15 to 30.

FIGS. 15, 18, 21 and 24 are layout views sequentially showing the liquidcrystal display of FIGS. 1 to 5 at an intermediate step in itsmanufacture. FIGS. 16, 19, 22, 25, 27, and 29 are sequentialcross-sectional views taken along line XVI-XVI, line XIX-XIX, lineXXII-XXII, and line XXV-XXV of the liquid crystal display of FIGS. 15,18, 21, and 24, and FIGS. 17, 20, 23, 26, 28, and 30 are sequentialcross-sectional views taken along line XVII-XVII, line XX-XX, lineXXIII-XXIII, and line XXVI-XXVI of the liquid crystal display of FIGS.15, 18, 21, and 24.

First, referring to FIGS. 15, 16, and 17, the plurality of gateconductors 121 and 125 (including the plurality of gate lines 121 havingthe gate electrodes 124 and the plurality of common voltage lines 125having the extension 126) are formed on the insulating substrate 110,and the gate insulating layer 140 is stacked thereon.

Next, referring to FIGS. 18, 19, and 20, a semiconductor layer (notshown), a semiconductor layer (not shown) doped with one or moreimpurities, and a data conductive layer (not shown) are sequentiallystacked on the gate insulating layer 140. Then, the plurality of linearsemiconductors 151 (including the semiconductor protrusion 154, theplurality of ohmic contacts 161 and 165, and the plurality of dataconductors which includes the plurality of data lines 171 having thesource electrode 173, and the plurality of drain electrodes 175) areformed by exposure and etching through a single mask.

Next, referring to FIGS. 21, 22, and 23, a transparent conductivematerial such as ITO, IZO, or the like is stacked on the data conductorand is etched, thereby forming the plurality of surface-type pixelelectrodes 191.

Next, referring to FIGS. 24, 25, and 26, the first passivation layer 180a, which can be made of an organic insulating material or an inorganicinsulating material, is stacked on the pixel electrode 191.

Then, organic material with a dielectric constant of about 3.5 or lessis stacked on the first passivation layer 180 a and a second passivationpattern 180 c 1 formed of an organic layer is formed by exposure anddeveloping.

The second passivation pattern 180 c 1 includes a thicker portiondisposed on the upper portion of the data line 171, and a thinnerportion having a lesser thickness than the thick portion.

As described above, as a method of making the thickness of the secondpassivation pattern 180 c 1 vary by position, a method of using a photomask with a translucent area may be employed.

When the second passivation pattern 180 c 1 has negativephotosensitivity (i.e. is more easily removed in portions where light isnot irradiated), the area A of the photo mask is translucent to transmita portion of light, the area B is transparent to transmit light, and thearea C is opaque to block light.

Therefore, among the second passivation pattern 180 c 1, the portioncorresponding to area A of the photo mask is formed to have a lowerthickness, a portion corresponding to area B is formed to have a higherthickness, and a portion corresponding to area C is removed.

The photo mask of the area A may include a pattern such as slits orlattice, or a translucent layer, in order to control the amount of lighttransmitted.

If the second passivation pattern 180 c 1 has positive photosensitivity,the transparency of the areas B and C of the photo mask is reversed.

Next, referring to FIGS. 27 and 28, the gate insulating layer 140 andthe first passivation layer 180 a are subjected to dry etching using thesecond passivation pattern 180 c 1 as a mask, thereby forming thecontact hole 182 to expose a portion of the common voltage line 125.

In this case, the thickness of the second passivation pattern 180 c 1over the entire substrate 110 may be made thinner as compared to theprevious thickness of the second passivation pattern 180 c 1 in thesteps shown in FIGS. 25 and 26.

Then, a transparent conductive material such as ITO, IZO, etc., isstacked on the second passivation pattern 180 c 1 and is etched, therebymaking it possible to form the plurality of common electrodes 131.

In this case, the second passivation pattern 180 c 1 may be a secondpassivation layer 180 b shown in FIGS. 1, 4, and 5 described above, andthe lower display panel 100 of the liquid crystal display shown in FIGS.1, 4, and 5 may be manufactured by the above-mentioned manufacturingmethod.

Meanwhile, further referring to FIGS. 29 and 30, at the steps of FIGS.27 and 28, only the thicker portion of layer 180 c 1 that issubstantially disposed on the data line 171 remains, with the remainingthin portion having been removed by ashing the second passivationpattern 180 c 1 entirely, thereby forming the second passivation layer180 c, which corresponds to FIGS. 1, 2 and 3 explained above.

Finally, referring to FIGS. 1 to 3, a transparent conductive materialsuch as ITO, IZO, etc., is stacked on the second passivation layer 180 cand is etched, thereby forming the plurality of common electrodes 131.

The lower display panel 100 of the liquid crystal display shown in FIGS.1, 2, and 3 may be manufactured by the above-mentioned manufacturingmethod.

In the exemplary embodiment of the present invention described above,the branch electrodes of the common electrode or the pixel electrode aresubstantially inclined at an angle that is closer to the verticaldirection (i.e. the extending direction of the data line) than thehorizontal, but embodiments of the invention are not limited thereto.Instead, the branch electrodes of the common electrode or the pixelelectrode may be inclined closer to the horizontal direction (i.e., theextending direction of the gate line).

For example, as shown in FIG. 31, the common electrode or the pixelelectrode according to another exemplary embodiment of the presentinvention may include at least one vertical stem part 138 that extendsin the vertical direction, and a plurality of branch electrodes 139connected thereto.

The plurality of branch electrodes 139 may form an angle larger thanabout 0 degree or smaller than about 45 degrees with respect to ahorizontal direction Dir1, wherein the horizontal direction Dir1 may bethe direction in which the gate line 121 generally extend, in theabove-mentioned exemplary embodiments.

Next, a liquid crystal display according to an exemplary embodiment ofthe present invention will be described with reference to FIGS. 32, 33,and 34. The same components as the above-mentioned exemplaryembodiments, in particular the exemplary embodiments shown in FIGS. 1 to5, are denoted by the same reference numerals. Accordingly, substantivedescription thereof will be omitted.

FIG. 32 is a layout view of one pixel of a liquid crystal displayaccording to an exemplary embodiment of the present invention and FIGS.33 and 34 each are cross-sectional views taken along line XXXIII-XXXIIIand line XXXIV-XXXIV of FIG. 32 respectively, according to the exemplaryembodiment of the present invention.

A liquid crystal display according an exemplary embodiment of thepresent invention includes a lower display panel 100 and an upperdisplay panel 200 that face each other, with a liquid crystal layer 3disposed between the two display panels 100 and 200.

First, describing the lower display panel 100, a plurality of gateconductors, including a plurality of gate lines 121 and a plurality ofcommon voltage lines 125, are formed on an insulating substrate 110. Agate insulating layer 140 is then formed on the gate conductors 121 and125. A plurality of linear semiconductors 151 are formed on the gateinsulating layer 140, and a plurality of linear ohmic contacts 161 and aplurality of island ohmic contacts 165 are formed on the linearsemiconductors 151. Data conductors, including a plurality of data lines171 and a plurality of drain electrodes 175, are formed on the ohmiccontacts 161 and 165.

A first passivation layer 180 x is disposed on the data conductors 171and 175 and the exposed semiconductor protrusion 154 of the linearsemiconductors 151, wherein the first passivation layer 180 x may bemade of an organic insulating material, an inorganic insulatingmaterial, or the like.

A second passivation layer 180 y is disposed on the first passivationlayer 180 x. The second passivation layer 180 y includes an organicmaterial and may be formed on substantially the entire surface of thesubstrate 110 while covering the data line 171.

The relative permittivity of the second passivation layer 180 y may be3.5 or less. There may be about 10% deviation in such relativedielectric constant of the second passivation layer 180 y, according tothe measuring method employed. When the second passivation layer 180 yincludes a colored material such as a material for color filters, therelative dielectric constant of the second passivation layer 180 y maybe increased to about 4.5, accounting for the relative dielectricconstant of the pigment or dye included in the colored material. Athickness of the second passivation layer 180 y may be in a range fromabout 0.5 μm to about 3.0 μm. The lower the relative permittivity of thesecond passivation layer 180 y is, the thinner the thickness of thesecond passivation layer 180 y may become. In the present exemplaryembodiment, the upper surface of the second passivation layer 180 y maybe approximately flat.

The first passivation layer 180 x and the second passivation layer 180 yhave a contact hole 181 formed therethrough, which exposes a portion ofthe drain electrode 175.

A plurality of pixel electrodes 191 are disposed on the secondpassivation layer 180 y. The pixel electrode may have an approximatelyplanar shape to fill most of the area surrounded by the gate lines 121and the data lines 171. The outer shape of the pixel electrode 191 maybe a polygon having sides approximately parallel with the gate lines 121or the data lines 171, and with both lower corners of the pixelelectrode 191 being chamfered. However, the shape of the pixel electrode191 is not limited thereto.

In operation, a data voltage is applied to the pixel electrode 191 fromthe drain electrode 175 through the contact hole 181.

A third passivation layer 180 z is disposed on the pixel electrode 191.The third passivation layer 180 z may be made of an inorganic insulatingmaterial, an organic insulating material, or the like. The thirdpassivation layer 180 z, the second passivation layer 180 y, the firstpassivation layer 180 x, and the gate insulating layer 140 have incommon a plurality of contact holes 182 that each expose a portion ofthe common voltage line 125 (for example, a portion of the extension126).

A plurality of common electrodes 131 are disposed on the thirdpassivation layer 180 z. Each common electrode 131 includes a pair ofvertical parts 135 that cover the data lines 171, a plurality of branchelectrodes 133 that are disposed between the two vertical parts 135 andthat are spaced apart from each other, and both a lower horizontal part132 a and an upper horizontal part 132 b connecting the end portions ofthe plurality of branch electrodes 133. The vertical part 135 isapproximately parallel to the data line 171 and overlaps (i.e. at leastpartially covers) the data line 171. The adjacent common electrodes 131are connected to each other while sharing a single horizontal part 135.

Next, describing the upper display panel 200, a light blocking member220 and a color filter 230 are disposed on the insulating substrate 210.

The light blocking member 220 includes a portion covering the areabetween two adjacent pixel electrodes 191, generally over the data line171. Therefore, the light blocking member 220 may cover the portion ofthe data line 171 extending between two adjacent pixel electrodes 191.The width of the light blocking member 220 covering the area between twoadjacent pixel electrodes 191 may be equal to or smaller than a distancebetween the two adjacent pixel electrodes 191. For example, a distanceD1 between an edge of the light blocking member 220 and an edge of theadjacent pixel electrode 191 may be 0 or more, and may be smaller than adistance between the two adjacent pixel electrodes 191. The lightblocking member 220 prevents light from being leaked between theadjacent pixel electrodes 191, and defines opening areas facing thepixel electrode 191.

An overcoat 250 may be further disposed on the light blocking member 220and the color filter 230.

Unlike the exemplary embodiment, at least one of the light blockingmember 220 and the color filter 230 may be disposed on the lower displaypanel 100.

The outside of the substrate 110 of the lower display panel 100 may befurther provided with a backlight unit (not shown) that generates lightand provides the light to the two display panels 100 and 200.

In the exemplary embodiment, the second passivation layer 180 y formedof an organic layer is interposed between the data line 171 and theoverlapping vertical part 135 of the upper common electrode 131. Thus,the parasitic capacitance of the data line 171 and the common electrode131 may be decreased, thereby making it possible to reduce the signaldelay of the data line 171.

FIGS. 35 and 36 each are cross-sectional views taken along lineXXXIII-XXXIII and line XXXIV-XXXIV of FIG. 32 respectively, according toanother exemplary embodiment of the present invention.

The liquid crystal display according to the exemplary embodiment shownin FIGS. 32, 35, and 36 is approximately the same as the exemplaryembodiment shown in FIGS. 32, 33, and 34 as described above, except forthe structure of the second passivation layer 180 y. For example, asshown in FIGS. 35 and 36, the second passivation layer 180 y is notformed on substantially the entire surface of substrate 110, but extendsalong the data line 171 while covering the data line 171. In this case,the contact holes 181 or the contact hole 182 as described above may notbe formed in the second passivation layer 180 y. As in the presentembodiment, the parasitic capacitance of the data line 171 and thecommon electrode 131 may be lowered by forming the second passivationlayer 180 y only on the data line 171, thereby making it possible toreduce the signal delay of the data line 171.

As in the exemplary embodiment of the present invention, the secondpassivation layer 180 y is formed only on the data line 171 and is notformed in a display area (for example, a pixel area, or an area wherethe pixel electrode 191 is formed between the two data lines 171), suchthat absorption of light from the backlight due to the organic secondpassivation layer 180 y may be reduced, thereby making it possible toprevent a reduction in transmittance.

The layer position of the first passivation layer 180 x and the secondpassivation layer 180 y may be switched. That is, layer 180 x mayinstead be formed on layer 180 y.

FIGS. 37 and 38 each are cross-sectional views taken along lineXXXIII-XXXIII and line XXXIV-XXXIV of FIG. 32 respectively, according toanother exemplary embodiment of the present invention.

The liquid crystal display according to the exemplary embodiment shownin FIGS. 32, 37, and 38 is approximately the same as the exemplaryembodiment shown in FIGS. 32, 33, and 34 as described above, except forthe structure of the second passivation layer 180 y. For example, asshown in FIGS. 37 and 38, the thickness of the second passivation layer180 y may vary by position. In more detail, the thickness of the portionof the second passivation layer 180 y extending along the data line 171may be thicker than other portions. When the permittivity of the secondpassivation layer 180 y is lowered, the thickness of the secondpassivation layer 180 y may be further reduced, and accordingly, defectsin the alignment layer 11 due to steps in the second passivation layer180 y or wiring defects such as disconnections may be prevented.

According to the exemplary embodiment of the present invention, when thethickness of the portion of the second passivation layer 180 y extendingalong the data line 171 is formed thicker than other portions, the delayin data signal due to parasitic capacitance between the data line 171and the common electrode 131 or between data line 171 and the pixelelectrode 191 may be reduced. Further, the absorption of light by theorganic second passivation layer 180 y may be reduced by reducing thethickness of the portions of the second passivation layer 180 y besidesthose portions extending along the data line 171. For example, theportion disposed where the pixel electrode 191 is formed may be thinned,thereby making it possible to prevent the reduction in transmittance.

In the various exemplary embodiments of the present invention shown inFIGS. 32 to 38, the position of the second passivation layer 180 y isnot limited to the positions shown, but instead may be disposed in anylayer if the second passivation layer 180 y is disposed between the dataline 171 and the common electrode 131. For example, the layer positionof the first passivation layer 180 x and the second passivation layer180 y may be switched.

Next, a liquid crystal display according to an exemplary embodiment ofthe present invention will be described with reference to FIGS. 39, 40,and 41. The same components in the above-mentioned exemplary embodimentsare denoted by the same reference numerals, and detailed descriptionthereof will be omitted.

FIG. 39 is a layout view of one pixel of a liquid crystal displayaccording to an exemplary embodiment of the present invention, and FIGS.40 and 41 each are cross-sectional views taken along line XL-XL and lineXLI-XLI of FIG. 39 respectively.

The present exemplary embodiment is approximately the same as theexemplary embodiment shown in FIGS. 32 to 34, except for the structureof the data line 171, the pixel electrode 191, and the common electrode131. Therefore, discussion focuses primarily on differences from theexemplary embodiments of FIGS. 32 to 34 described above.

The data line 171 according to the present exemplary embodiment of thepresent invention is periodically bent (i.e. bent in places) and formsan oblique angle with the direction of extension of the gate line 121.The oblique angle of the data line 171 to the extending direction of thegate line 121 may be 45° or more if desired.

The first passivation layer 180 x and the second passivation layer 180 yare disposed on the data conductors 171 and 175 and the exposedsemiconductor protrusion 154. The first passivation layer 180 x, thesecond passivation layer 180 y, and the gate insulating layer 140include contact holes 184 that respectively expose portions of thecommon voltage line 125. The second passivation layer 180 y may includean organic material and have a relative permittivity of 3.5 or less.There may be about 10% deviation in such relative dielectric constant ofthe second passivation layer 180 y depending on the measuring methodemployed. Representative characteristics of the second passivation layer180 y may be the same as those of the second passivation layer 180 y ofthe exemplary embodiment shown in FIGS. 32 to 34 described above.

A common electrode 131 m is disposed on the second passivation layer 180y. The common electrode 131 m is electrically connected to the commonvoltage line 125 through the contact hole 184, to be applied with apredetermined voltage such as the common voltage Vcom from the commonvoltage line 125. In the present exemplary embodiment, the commonelectrode 131 m, which has an approximately planar shape, may be formedon substantially the entire surface of the substrate 110 as a singleplatelike structure.

The third passivation layer 180 z is disposed on the common electrode131 m and a pixel electrode 191 m is disposed thereon. A plurality ofcontact holes 183 that respectively expose portions of the drainelectrode 175 are formed in the first passivation layer 180 x, thesecond passivation layer 180 y, and the third passivation layer 180 z.The pixel electrode 191 m is electrically connected to the drainelectrode 175 through the contact hole 183, so as to be supplied withthe data voltage. The pixel electrode 191 m includes a plurality ofbranch electrodes 193 m extending substantially parallel to each otherand spaced apart from each other, and lower and upper horizontal parts192 m that connect the top or bottom end portions of the branchelectrodes 193 m. The branch electrodes 193 m of the pixel electrode 191m may be bent along with the data line 171, as shown.

When a data voltage is applied to pixel electrode 191 m, it generates anelectric field in the liquid crystal layer 3 together with the commonelectrode 131 m (which has the common voltage applied to it).

The common electrode 131 m covers a plurality of data lines 171 at atime and overlaps the data lines 171. Therefore, crosstalk between thedata line 171 and the pixel electrode 191 may be reduced, and lightleakage due to parasitic capacitance between the data line 171 and theadjacent pixel electrode 191 may also be reduced.

In addition, the organic second passivation layer 180 y is disposedbetween the data line 171 and the common electrode 131 m to lower theparasitic capacitance between the data line 171 and the common electrode131 m, thereby making it possible to reduce the signal delay of the dataline 171. The thickness of the second passivation layer 180 y may befurther thinned, and the signal delay of the data line 171 may reduced,by lowering the relative permittivity of the second passivation layer180 y.

Various characteristics and effects of the previous exemplaryembodiments shown in FIGS. 32 to 34 may be also applied to the presentexemplary embodiment.

FIGS. 42 and 43 each are cross-sectional views taken along line XL-XLand line XLI-XLI of the liquid crystal display of FIG. 39 respectively,according to another exemplary embodiment of the present invention.

The liquid crystal display according to the exemplary embodiment shownin FIGS. 39, 42, and 43 is approximately the same as the exemplaryembodiment shown in FIGS. 39, 40, and 41 as described above, except forthe structure of the second passivation layer 180 y. For example, asshown in FIGS. 42 and 43, the second passivation layer 180 y is notformed on substantially the entire surface of substrate 110, but extendsalong the data line 171 while covering the data line 171. In this case,the contact holes 181 or the contact holes 183 described above may notbe formed in the second passivation layer 180 y. As such, the parasiticcapacitance between the data line 171 and the common electrode 131 maybe lowered by forming the second passivation layer 180 y only on thedata line 171, thereby making it possible to reduce the signal delay ofthe data line 171.

FIGS. 44 and 45 each are cross-sectional views taken along line XL-XLand line XLI-XLI of the liquid crystal display of FIG. 39 respectively,according to another exemplary embodiment of the present invention.

The liquid crystal display according to the present exemplary embodimentshown in FIGS. 39, 44, and 45 is approximately the same as the exemplaryembodiment shown in FIGS. 39, 40, and 41 as described above, but thethickness of the second passivation layer 180 y may vary by position.For example, the thickness of the portion of the second passivationlayer 180 y extending along the data line 171 may be relatively thickerthan other portions.

In the various exemplary embodiments of the present invention shown inFIGS. 39 to 45, the position of the second passivation layer 180 y isnot limited to those shown. For example, the layer position of the firstpassivation layer 180 x and the second passivation layer 180 y may beswitched.

Various characteristics and effects of the exemplary embodimentdescribed above may be also applied to the exemplary embodiment havingthe same components.

FIGS. 46, 47, 48, 49, and 50 each are layout views of a liquid crystaldisplay according to an exemplary embodiment of the present invention.

First referring to FIG. 46, the liquid crystal display according to thepresent exemplary embodiment of the present invention is approximatelythe same as the liquid crystal display shown in FIGS. 39 to 45 describedabove.

The data line 171 and the pixel electrode 191 m of the liquid crystaldevice according to the present exemplary embodiment may be bent atleast once between two adjacent gate lines 121, as shown. In detail,referring to FIG. 46, the data line 171 and the branch electrode 193 mof the pixel electrode 191 m may be bent approximately at the middleportion between the two adjacent gate lines 121 and may be bent again attwo points above and under the bent point of the middle portion. Inaddition, the data line 171 and the branch electrode 193 m of the pixelelectrode 191 m may be bent in the vicinity of the lower and upperhorizontal parts 192 m of the pixel electrode 191 m. As such, the dataline 171 and the branch electrode 193 m of the pixel electrode 191 m arebent respectively once each in the vicinity of the lower and upperhorizontal parts 192 m or are bent third times at the middle portionbetween the two adjacent gate lines 121, thereby making it possible toreduce texture occurring when the inclination direction of the liquidcrystal molecules is not controlled.

Next, referring to FIG. 47, the liquid crystal display according to thepresent exemplary embodiment is approximately the same as the liquidcrystal display shown in FIG. 46. In the liquid crystal displayaccording to the present exemplary embodiment, each of the differentpixel electrodes 191 m may have the same shape. For example, all theconvex points at the bent portions of the branch electrodes 193 m of thepixel electrodes 191 m that are adjacent in a row direction or columndirection may be disposed at a same side with respect to the pixelelectrodes 191 m (all the convex points of the branch electrodes 193 mface to the left in FIG. 47). Therefore, all of the plurality of datalines 171 may be periodically bent such that the data lines 171 protrudein one direction.

In addition, the liquid crystal display according to the presentexemplary embodiment includes thin film transistors positioned both tothe left and right of a data line 171. The TFTs positioned at the leftside and the TFTs positioned at the right side with respect to the dataline 171 may be 1×1 alternately arranged along the column direction. Allthe TFTs disposed in a single row may be positioned at one side withrespect to the data line 171.

In the liquid crystal display according to the present exemplaryembodiment, the common electrode (not shown, but the same as the commonelectrode 131 m shown in FIGS. 40 to 45) is connected to the commonvoltage line 125 through the contact holes 184. As shown in FIG. 47, oneor two contact holes 184 may be arranged per three pixel electrodes 191m.

Next, referring to FIG. 48, the liquid crystal display according to thepresent exemplary embodiment is approximately the same as the liquidcrystal display shown in FIG. 47. However, unlike the exemplaryembodiment shown in FIG. 47, the TFTs positioned at the left side andthe TFTs positioned at the right side with respect to a data line 171may be arranged 2×2 alternately along the column direction. All the TFTsdisposed in a row may be positioned at one side with respect to the dataline 171.

Next, referring to FIG. 49, the liquid crystal display according to thepresent exemplary embodiment is approximately the same as the liquidcrystal display shown in FIG. 47. However, in the present exemplaryembodiment of the present invention, the shapes of the pixel electrodes191 m adjacent in the column direction are different from each other. Indetail, the bending direction of the branch electrodes 193 m of the twopixel electrodes 191 m adjacent in a row direction may be different. Thepixel electrode 191 m having the convex point of the bent portion of thebranch electrodes 193 m at the left side and the pixel electrode 191 mhaving the convex point at the right side may be 1×1 alternatelyarranged along the column direction. Therefore, the data line 171includes a portion bent to the left and a portion bent to the right,that are arranged alternately.

Next, referring to FIG. 50, the liquid crystal display according to thepresent exemplary embodiment of the present invention is approximatelythe same as the liquid crystal display shown in FIG. 49. However, unlikethe exemplary embodiment shown in FIG. 49, the TFT positioned at theleft side and the TFT positioned at the right side with respect to adata line 171 may be arranged 2×2 alternately along the columndirection. All the TFTs in a row may be positioned at one side withrespect to the data line 171.

While this invention has been described in connection with what ispresently considered to be practical exemplary embodiments, it is to beunderstood that the invention is not limited to the disclosedembodiments, but, on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the appended claims.

<Description of symbols>  3: Liquid crystal layer  31: Liquid crystalmolecule 110, 210: Substrate 100, 200: Display panel 121: Gate line 124:Gate electrode 125: Common voltage line 131, 131m: Common electrode 140:Gate insulating layer 151, 154: Semiconductor 161, 163, 165: Ohmiccontact 171: Data line 173: Source electrode 175: Drain electrode 180a,180b, 180c, 180d: Passivation layer 181, 182, 183, 184: Contact hole191, 191m: Pixel electrode 131, 131m: Common electrode 220: Lightblocking member 230: Color filter 250: Overcoat

What is claimed is:
 1. A liquid crystal display, comprising: a firstsubstrate and a second substrate overlapping each other; a liquidcrystal layer interposed between the first substrate and the secondsubstrate; a first data line disposed between the first substrate andthe second substrate; a first passivation layer including an inorganicmaterial and disposed on the first data line; a second passivation layerincluding an organic material and disposed on the first passivationlayer; a common electrode disposed on the second passivation layer andoverlapping the first data line; a pixel electrode disposed in a layeron the second passivation layer and not overlapping the first data linein a direction perpendicular to a surface of the first substrate; and athird passivation layer disposed between the common electrode and thepixel electrode, wherein the first passivation layer, the secondpassivation layer, and the third passivation layer are positioned in alayer-between the first data line and the pixel electrode in thedirection perpendicular to the surface of the first substrate, thesecond passivation layer includes a first portion disposed between thecommon electrode and the first data line in a direction perpendicular toa bottom surface of the first substrate, the second passivation layerincludes a second portion overlapping the pixel electrode, and a maximumthickness of the first portion perpendicular to an extension directionof the first portion is greater than a maximum thickness of the secondportion perpendicular to an extension direction of the second portion.2. The liquid crystal display of claim 1, wherein: a dielectric constantof the second passivation layer is smaller than a dielectric constant ofthe first passivation layer.
 3. The liquid crystal display of claim 2,wherein: the dielectric constant of the second passivation layer isabout 3.5 or less.
 4. The liquid crystal display of claim 3, wherein:liquid crystal molecules of the liquid crystal layer are alignedsubstantially parallel to a surface of the first substrate in an absenceof an electric field in the liquid crystal layer.
 5. The liquid crystaldisplay of claim 4, further comprising: a drain electrode disposed in asame layer as the first data line and opposing a source electrode of thedata line, wherein the first passivation layer and the secondpassivation layer includes a contact hole exposing the drain electrode,and the pixel electrode is connected to the drain electrode through thecontact hole.
 6. The liquid crystal display of claim 1, furthercomprising: a second data line adjacent to the first data line andextending substantially in a same direction as the first data line;wherein the second passivation layer further includes a third portiondisposed between the common electrode and the second data line.
 7. Theliquid crystal display of claim 6, wherein: the first portion and thethird portion are separated from each other.
 8. The liquid crystaldisplay of claim 7, wherein: a dielectric constant of the secondpassivation layer is smaller than a dielectric constant of the firstpassivation layer.
 9. The liquid crystal display of claim 8, wherein:the dielectric constant of the second passivation layer is about 3.5 orless.
 10. The liquid crystal display of claim 9, wherein: liquid crystalmolecules of the liquid crystal layer are aligned substantially parallelto a surface of the first substrate in an absence of an electric fieldin the liquid crystal layer.
 11. The liquid crystal display of claim 10,further comprising: a drain electrode disposed in a same layer as thefirst data line and opposing a source electrode of the first data line,wherein the first passivation layer and the second passivation layerincludes a contact hole exposing the drain electrode, and the pixelelectrode is connected to the drain electrode through the contact hole.12. The liquid crystal display of claim 6, wherein: the second portionof the second passivation layer connects the first portion and the thirdportion.
 13. The liquid crystal display of claim 12, wherein: adielectric constant of the second passivation layer is smaller than atleast one of 3.5 and a dielectric constant of the first passivationlayer.
 14. The liquid crystal display of claim 1, further comprising: alight blocking member overlapping the first data line, wherein a widthof the light blocking member is greater than a width of the first dataline.